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The Ferx Lover's Compaxiox 



Oak Fern. Phrgoptcris Dri/optcri.^ 



fine species for cultivation at the base of the artificial 

 rockery. 



(2) The Northern Oak Ferx 



Phegopteris Rohertiana. Phegopteris calcarea 



Thelypteris Robertiana 



Resembles the oak fern, but with fronds rather larger, 

 especially the terminal segment; also more rigid and 

 coarser in appearance. Stalks and fronds minutely glandu- 

 lar beneath. Lower pinnules of the lateral divisions 

 scarcely longer than the others. Often called "Limestone 

 Polypody," the beech ferns having formerly been classed 



